Fastening



April 21, 1936. F. N. LA CHAPELLE FASTENING Filed Dec. 2'7, 1934 Patented Apr. 21, 1936 hrr FASTENKNG Application lllecemher 2'7, i934, Serial No. 759,332

12 @iaims.

This invention relates to improvements in lastenings and is shown herein, by way of illustration, as embodied in staples formed from twisted paper impregnated with glue or other suitable 5 stiffening material.

Staples formed of felted fibrous material such as paper or" the type disclosed in United States Letters ?atent No. 1,957,216, granted May 1, 1934, on an application filed in the name of Fred N. La Chapelle, under most conditions, form eifective fastenings for securing together, either temporarily or permanently, parts of leather or other work pieces. Under some conditions, particularly when staples having relatively short bars are formed, there is a tendency for the fastening material to crack adjacent to the bends at the junctures oi the bar and the legs of the staple. This is due to the fact that the felted fibrous material is stiff and rigid and the material must stretch along the outer portion of the bend and be compressed along the inside portion of the bend. When the bend is sharp the material is sometimes stretched beyond its elastic limit withthe result above noted. When this occurs the holding power 25 of the staple is materially reduced and a substantial strain applied to the work may cause the bar of the staple to part or break away from one or both of the staple legs.

An object ofthe present invention, accordingly, is to provide an improved fastening by the use of which the abovementioned difficulties will be overcome. In accordance with this object a feature of this invention resides in a driven fastening having an outer layer of relatively hard and rigid paper material and a core of flexible reinforcing material. As illustrated, the outer covering is composed of paper impregnated with sizing material, for example, glue, and the core is formed of thread spun or twisted from textile fibre.

Since the problems solved by this invention arose in the use of staples formed of twisted sized paper,-the invention is illustrated herein with special reference to staples but it should be understood that the utility of the invention is not so limited since it is apparent that other types of fastenings, for example, pegs, could be formed of fastening material of this character, if desired.

With the above and other objects in view, the invention will now be described in connection with the accompanying drawing and pointed out in the appended claims.

In the drawing, v

Fig. 1 is a view on a much enlarged scale of a staple illustrating a preferred embodiment of the present invention;

Fig. 2 is a view in cross section taken along the line II-II of Fig. i;

Fig. 3 is a view, partly in section, on an enlarged scale of the material from which the fastenings are made;

Fig. 4 is a perspective view showing a portion of a machine for forming the fastening material; and

Fig. 5 is a view in vertical cross section of the portion of the machine shown in Fig. 4;

Material from which staples or other fastenings comprising a preferred embodiment of the invention may be made is illustrated in Figs. 1, 2 and 3 as composed of a relatively hard outer portion ill and a strong flexible core l2. The outer portion it is formed from twisted paper or other felted, fibrous material impregnated with glue or other suitable sizing which imparts to the material the requisite rigidity to withstand the hammering action of a fastening driving tool. The core l2 is in the form of a strong cotton or linen thread but it is evident that the core l2 could be made, if desired, of other material having substantial tensile strength and, preferably but not necessarily, soft and yielding.

This cored fibre fastening material, while it can successfully be used for fastenings such as pegs, is particularly adapted for use in making staples. As shown in Fig. 1 a staple Id is formed of the material. The staple M is provided with legs it which penetrate the work and which are con nected together by a bar I 8. As suggested above, the legs l6 of the staple I l are sufliciently rigid to be driven into holes formed in a work piece without breaking or crippling. When the staple I4 is formed, the material is bent about an inside former, and since the diameter of the fastening material is relatively large as compared with staple wire, the fastening material must stretch along the outside portion adjacent to the juncture of the legs and the bar, or the material must be compressed alongthe inner portion of the staple adjacent to the juncture of the legs and the bar, or both. When solid fibre fastening material is used this tendency to compress or stretch is noticeable particularly when staples having short bars are being formed and this stretching or compressing tendency sometimes results in cracking or breaking the material at the ends of the staple bar. However, when fibre fastening material having a relatively soft core is used in forming staples, the core I2 is compressed. or deformed adjacent to the juncture of the legs and the bar. The material .is flattened as shown in core I! is sufliciently soft to permit this deformation without any objectionable stretching or compressing of the material 10 and consequently the tendency of the material to crack or break is reduced to a minimum.

When a staple formed in this manner is driven into the work and the bar I8 of the staple is driven against the surface of the work, the effectiveness of the staple is not destroyed even though, as may happen in some cases, the felted fibrous or paper covering I0 is cracked or broken. In such cases, the core l2 acts to hold the parts of the staple H together thereby preventing the legs it of the staple from pulling through the work. After a. staple has been inserted in the work, the legs 16 may be trimmed or deflected toward the surface of the work to prevent the staple legs from being pulled back through the work.

In Figs. 4 and 5 is shown a portion of the machine disclosed in United States Letters. Patent No. 1,837,433,,granted December 22, 1931, on an application filed in the name of Alex Hayner.

' This machine as disclosed in said Letters Patent is designed particularly for forming fastening material from strips of paper. A paper strip 20 is passed through a bath of glue 22 or other suitable sizing material under a guide bar 24 and about a vertical rod 26 which serves to guide the paper strips 20 to a die 28. Located above the die 28 is a mechanism arranged to impart the desired twist to the paper. This mechanism is substantially the same as that disclosed in the above-mentioned Letters Patent to which reference may be had for a detailed description of the twisting mechanism. The vertical rod 26 is hollow and serves to guide the core material, illustrated as a thread 30, to the paper as it is being twisted. The thread 30 is wound on a spool 32 which may be mounted on a suitable support 34. As the paper is twisted the thread 30 is pulled from the spool through a guiding eye 38 and into the hollow rod 26, the paper being twisted about the thread 30. After the fastening material has been subjected to the preliminary twisting operation it may be further twisted and passed through stripping dies as disclosed in said Letters Patent. After these operations the material may be formed into fastenings such, for example, as staples or pegs.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. A driven fastening having an outer layer of relatively rigid paper material reinforced with a core of flexible material,

2. A driven fastening having a core of twisted fibrous material covered with felted fibrous material sized with a stiffening material.

3. A driven fastening having a thread 'core,

covered with paper impregnated with glue.

4. A staple of felted fibrous material reinforced with a thread core.

5. A staple having a core of twisted fibrous material.

6. A staple'formed of felted fibrous material and twisted fibrous material.

'7. A staple having a core of twisted fibrous material covered by felted fibrous material.

8. A staple having a core of twisted fibrous material covered with felted fibrous material sized with a stiffening material.

9. A staple having a core of twisted fibrous material covered with a felted fibrous material sized with glue.

10. A staple having a core of twisted fibrous material covered with paper impregnated with glue.

11. A staple having a thread core covered with paper.

12. A staple having a thread core covered with paper impregnated with glue.

FRED N. LA CHAPEILE. 

